kenney



Feb. 21, 1956 LIQUID Filed June 10, 1952 C. E. KENNEY SUPPLY MEANS FOR AROTARY MACHINE 3 Sheets-Sheet l Feb. 21, 1956 c. E. KENNEY 2,735,367LIQUID SUPPLY MEANS FOR A ROTARY MACHINE Filed June 10, 1952 3Sheets*Sheet 2 Feb. 21, 1956 c, KENNEY 2,735,367

I LIQUID SUPPLY MEANS FOR A ROTARY MACHINE Filed June 10, 1952 5Sheets-Sheet 3 United States Patent 2,735,367 LIQUID SUPPLY MEANS FOR AROTARY MACHINE Clarence E. Kenney, Hartlaud, Wis., assignor to Allis-Cllalmers Manufacturing Company, Milwaukee, Wis.

Application June 10, 1952, Serial No. 292,763 Claims. c1. 103-4 Thisinvention relates to a liquid impelling device of novel design and alsoto a pressure liquid supply system for a rotating machine which systemembodies the novel impelling device. More particularly, this inventionrelates to a novel liquid supply system for a prime mover which systemfurnishes a sufiicient quantity of low pressure liquid for lubricationpurposes and a sufficient quantity of high pressure liquid for operatingthe hydraulic governing apparatus of the prime mover. The presentimpelling device and supply system are particularly useful with steamturbines which require a supply of pressure liquid sufiicient tolubricate bearing surfaces and to actuate safety governing units.

Rotating prime movers such as steam turbines have heretofore beenlubricated and otherwise supplied with pressure liquid by systemsembodying one or more pumps geared to the turbine shaft. However, theseknown systems have not been entirely satisfactory because of thecomplicated and costly arrangement of auxiliary apparatus deemedessential to insure the continuous and safe operation of the turbine. 7

Moreover the known systems embodying pumps having an indirect connectionwith the turbine shaft have proven suificiently troublesome so thatattempts have been made to mount at least one of the pumps directly onthe turbine shaft and drive the other pumps by suitable auxiliary means.Of course, the particular problems incident to mechanical gearing aresolved if all of the oil pumps are driven by auxiliary driving means.However, such an arrangement is only as reliable as the auxiliarydriving means and consequently a failure of the auxiliary driving meansfor any reason while the turbine is running will obviously result in astoppage of lubrication and possible failure of the bearings. A bearingfailure will probably end operation of the hydraulic governingapparatus, with the result that there may be overspeeding and consequentdamage to the turbine.

The present invention avoids the aforementioned and other disadvantagesby providing an improved system incorporating elements combined forcoaction in a novel manner wherein one of the elements may be a doublevolute centrifugal pump of novel design mountable directly on a primemover shaft in a manner insuring eflicient and trouble free operation.

The use of a double volute pump in a system of the type mentionedeliminates the necessityfor employing additional cumbersome apparatusfor supplying liquid to a machine in considerable volume at twodifferent pres sures. The novel design of this pump also permits theprime mover shaft upon which it is mounted to expand and contractaxially without deleteriously affecting the operation of the pump in anymanner.

Accordingly an object of this invention is toprovide an improved systemfor effectively supplying a liquid, such as oil, to a rotating machineat different pressures essential for its safe operation, the systemembodying a simplified and novel combination of apparatus minimizingthenumber of elements essential for attaining such operation.

Another object is to provide a novel design of a double volutecentrifugal pump which can be operatively mounted directly on the primemover shaft and which incorporates parts constructed and combined forcoaction in an improved manner insuring efficient and trouble freeoperation.

Still another object of this invention is to provide an improved pump ofthe type above mentioned wherein the impellers are mounted on theturbine shaft in such a manner that axialexpansion of such shaft causesthe impellers and volutes of the pump to move simultaneously with theshaft, thereby maintaining a desired and uniform clearance between thecoacting stationary and movable parts.

Other objects and advantages will be apparent from the followingdescription with the accompanying drawings, in which:

Fig. 1 is a schematic illustration of an improved system for supplying aliquid at different pressures to the bearings and regulating apparatusof a rotating prime mover;

Fig. 2 is an enlarged section taken along the line 11-- II of Fig. 3 ofthe main pump shown in Fig. 1;

Fig. 3 is a plan view of the main pump shown in Fig. 2, a part of thetop of the casing being removed;

Fig. 4 is a section of the main pump taken on the line IV-IV of Fig. 2;and

Fig. 5 is a section of line V-V of Fig. 2.

As shown in the drawings in which like elements are designated by likenumerals, the system embodying the invention is disclosed as applied(note Fig. 1) to a steam turbine indicated generally at 6 and having arotating shaft 7 upon which a main liquid supply pump 8 is mounted.

As shown particularly in Figs. 25, pump 8 comprises a stationary casing9 through which the shaft 7 extends, the casing 9 being anchored on afoundation 11 which is common to the pump 8 and the turbine 6. Thecasing 9 is partitioned to provide three interior chambers, A, B and Caxially spaced from the turbine.

Mounted upon the shaft 7 within the casing 9 is an impeller assemblycomprising a runner 12 common to a high pressure impeller 13 and a lowpressure impeller 14. This assembly is secured at either of its ends tothe shaft 7 by keys 16 and 17, which hold the assembly in a relativelyfixed circumferential position thereon. J

A runner face 18, which is disposed adjacent the turbine side of thepump, coacts with a shoulder portion 19 on the shaft 7. An oppositelydisposed runner face 21 coacts with a nut 22 which is threaded to theouter end of shaft 7. The nut 22 secures the impeller assembly in afixed axial position on the shaft 7. Packing seals 23 are located at alljoints between the impeller runner 12 and the stationary casing 9.

A high pressure volute 24 is disposed around the high pressure impeller13, within the chamber A of the casing 9, this volute being providedwith packing seals 26 at all joints between it and the high pressureimpeller 13. The volute 24 has protruding flange portions 27 whichterminally engage thecasing 9 in a manner keying volute 24 againstrotation with impeller 13 and shaft 7 while allowing free axial movementof the volute relative to the casing. Volute 24 discharges liquid fromtwo diametrically opposite discharge passages 28 and 29 into chamber Aas shown in Fig. 4.' A conduit 31 leads from chamber A through a one waycheck valve 33 to the turbine elements which require a high pressuresupply of liquid, including elements in the hydraulic governing system32.

A low pressure volute 34 coacts with the low pressure impeller 14,within the chamber C of easing 8, and is the main pump taken on the2,735,367 r W e equipped with packing seals 36 at all joints between itand-the lowpressure impeller 14. The volute 34.. has protruding flangeportions 37 which terminally engage casing 9 in a manner keying volute34 to the casing in exactly the same manner as previously described withrespect to volute 24. Volute 34 discharges liquid from a passage 38 tothe chamber C in casing 9. A conduit 39 conducts liquid fromthe chamberC through a one way check valve 42 tom oilcooler 41, and thence througha pressure reducing valve 43 and conduit 40 to turbine elements, such.as turbine bearing portions 44, requiring a low pressure supplyofliquid. Valve 43 serves to maintain the bearing liquid at a fixed evenlow pressure.

The chamber B in casing 9 constitutes a liquid sump from which impellers13 and'14 are primed and otherwise supplied with oil. A conduit 46 leadsinto chamber B from an oilreservoir 47: this conduit includes a one waycheck valve 48. A bafiie plate 49 is disposed in chamber B toprevent-turbulence of the liquid in the sump as it is fed thereinto fromconduit 46.

With the pump construction thus far described, the runner 12 andimpellers 13 and 14 are fixed on shaft 7 for rotation therewith and moveaxially as a unit as the shaft 7 expands and contracts due totemperature changes.

The volutes 24 and 34 are connected to the impellers 13- and 14 bysuitable seals 26 and 36, which afford rotation ofthe impellers-relativeto the volutes.

When the turbine 6 heats up, shaft 7 expands axially, causing an axialdisplacement of the shoulder 19, which exerts a pressure on runner face18 effective to force the impeller assembly including runner 12,impellers 13 and 14, and volutes 24 and 34, to move axially with theshaft 7. As the turbine 6 cools down and shaft 7 contracts, the coactionbetween the nut 22 and the runner face 21 forces the impeller assemblyagain to move axially with the shaft 7. Casing is designed with internalclearances sufficient to allow the impeller assembly to unobstructedlymove longitudinally therewithin between limits determined by the hot andcold positions of the shaft 7.

As shown in Fig. l, conduit 31 leading from chamber A includes a branch51 which extends into reservoir 47 and terminates in nozzle 52positioned in an ejector pumping relation to the lower end of conduit46. Conduit 39 leading from chamber C is provided with a branch 53 whichextends into the reservoir 47 and is connected with the discharge of anauxiliary pump 54 operatively mounted in the reservoir 47. Branch 53 isprovided with a one way check valve 56 and with a pressure reducingdevice 57, which is positioned in downstream relation from valve 56,considering pump 54 as being disposed in upstream relation to the valve.In addition, a short conduit 58 places branch 51, of conduit 31, incontinuous communication with conduit 53 at a point between reducingvalve 57 and check valve 56.

Pump 54 is driven by shaft 59 operatively connected with an electricmotor 61 which is connected in turn with a suitable power source (notshown) through an automatic switch 62 and a manually actuated switch 63.Switch 62 is actuated by a diaphragm device 64 having a pressureconnection with high pressure conduit 31 through a branch conduit 66.The operation of the diaphragm device 64 is such that switch 62 is heldopen so long as the pressure in branch conduit 66 is in excess of apredetermined amount.

To take care of overflow oil from turbine bearing portion 44, a conduit67 extends between the bearing portion 44 and the reservoir 47, andconducts liquid from the bearing to the reservoir as it is forced out ofthe hearing by the inflow of liquid thereto from conduit 40.

With the parts positioned as shown in Fig. 1, it will be understood thatthe turbine 6 is operating normally and therefore the pump 8 isproducing sufiicient liquid flow to lubricate the bearings and operatethe hydraulic governing apparatus of the turbine. Under these conditionsthe pressure in branch conduit 66 which pressure is transmitted to thediaphragm device 64 is of a value elfectiveto maintain. switch 62in, an,openposition so .that.

motor 61 and pump 54 are not running. If for any reason the pressure inbranch conduit 66 falls below a predetermined value, the diaphragmdevice 64 will act to close switch 62, starting motor 61 and pump 54.The discharge of pump 54 serves to supplement or replace the flow ofpump 8 and thereby furnish liquid for lubrication and governoroperation: as aforementioned.

The manually actuated switch-63 is always closed while the turbine 6.isrunning, but is opened during periods ofturbine shutdown since durmgsuch periods there is no need for pressure liquid to lubricate theturbine or operate its hydraulic governing-apparatus.

This improvedvliquid supply system provides an oil supply at acomparatively high pressure for operating hydraulic devices such asgoverning units, and provides also an oil supply at a much lowerpressure for lubrication purposes. This is'all accomplished by means ofthe simplified system hereinbefore described which may include aunitarydouble volute pump coupled directly tothe shaft of the prime.moverwithout intermediate gearing. The effectiveness of the system ismaterially increased by the inclusion-and operation of a pump whichisnot deleteriously affected by expansion or contraction of the primemover shaft due-to changes in the temperature thereof. Such a pumpincludes features which are of more general application then that hereindisclosed byway of example;

Accordingly it should be understood that the invention is not intendedto be limited to the exact details of design, construction and/orcombination described herein for purposes of illustration, as variouschanges andmodifications within the scope of the appended claims may beapparent to those skilled inthe art.

It is claimed and desired to secure by Letters Patent: 1. In a machinehaving a rotary shaft portion projecting therefrom, the combinationcomprising:

spaced volute elements operatively surrounding saidrunner elements;stationary casing means sealingly enclosing said pump means and havinginternal partitions coacting with said volute and runner elements toform a separate discharge chamber for each of said volute elements and acommon inlet chamber intermediate said separate discharge chambers; saidstationary casing having oppositely disposed wall portions extendingsubstantially parallel to said shaft and a longitudinally extending slotin each wall portion, means provided on each of said volute elements inslidable engagement with said slots'in said Wall portions nonrotatablysupporting said volute elements for limited movement axially of saidshaft; and seal means interposed between and operatively unitingsaidrunner'and' volute elements for rotation of said runner relative to saidvolute elements.

2. In a machine having a rotary shaft portion projecting therefrom, thecombination comprising: dual pump meansincluding a pair of runnerelements fixed on said shaft for movement therewith and having outerportions spaced axially from each other and inner hubportions andseparate liquid discharge chambers disposed on axially opposite sides ofsaid inlet chamber, said stationary casing having oppositely disposedwall portions extending substantially parallel to said shaft and alongitudinallyextending slot in each wall portion, flange.

means provided oneach ofsaid volute elements in slidable engagementwithsaid slot in said wall portions nondual pump means including a pairof runner elements fixed p. v. m,

rotatably supporting said volute elements for limited movement axiallyof said shaft; and seal means interposed between and operatively unitingsaid runner and volute elements for rotation of the former relative tothe latter.

3. In a machine having a rotary shaft portion projecting therefrom, thecombination comprising: dual pump means comprising a pair of pumps eachincluding a runner element mounted on said shaft portion to turn andmove axially therewith and a volute element peripherally surroundingsaid runner element; stationary casing means sealingly enclosing saidpump means and having internal partitions coacting with said volute andrunner elements to form a common inlet chamber and separate liquiddischarge chambers, one for each of said volute elements, saidstationary casing having oppositely disposed wall portions extendingsubstantially parallel to said shaft and a longitudinally extending slotin each wall portion, a pair of laterally opposed flanges provided oneach of said volute elements in slidable engagement with said slots insaid wall portions nonrotatably supporting said volute elements forlimited movement axially of said shaft; and seal means interposedbetween and operatively uniting said runner and volute elements forrotation of the former relative to the latter.

4. In a machine having a rotary shaft portion projecting therefrom, acombination comprising: pump means including a runner element mounted onsaid shaft portion to turn and move axially therewith and a volutecasing peripherally surrounding said runner element; a stationary outercasing sealingly enclosing said pump means, said stationary casinghaving oppositely disposed wall portions extending substantiallyparallel to said shaft and a longitudinally extending slot in each wallportion; said pump means having oppositely disposed wall portions injuxtaposed relation to the wall portions of said stationary casing andflange means on the wall portions of said pump means in slidable keyedengagement with said slots in said wall portions for nonrotatably supporting said volute casing for limited movement axially of said shaft.

5. In a machine having a rotary shaft portion projecting therefrom, acombination comprising: pump means including a runner element mounted onsaid shaft portion to turn and move axially therewith and a voluteelement peripherally surrounding said runner element; stationary casingmeans sealingly enclosing said pump means and having internal partitionmeans coacting with said volute and runner elements to form an inletchamber and a liquid discharge chamber for-said volute element, saidstationary casing having oppositely disposed wall portions extendingsubstantially parallel to said shaft and a longitudinally extending slotin each wall portion; and volute support means provided on the peripheryof said volute element in slidable engagement with said slots in saidwall portions for nonrotatably supporting said volute element forlimited movement axially of said shaft.

6. In a machine having a rotary shaft portion projecting therefrom, acombination comprising: pump means including a runner element mounted onsaid shaft portion to turn and move axially therewith and a voluteelement peripherally surrounding said runner element; stationary casingmeans sealingly enclosing said pump means and having internal partitionmeans coacting with said volute and runner element to form an inletchamber and a liquid discharge chamber for said volute element, saidstationary casing having oppositely disposed wall portions extendingsubstantially parallel to said shaft and a longitudinally extending slotin each wall portion; and flange means provided on said volute elementin slidable keyed engagement with said slots in said wall portions fornon-rotatably supporting said volute element for limited movementaxially of said shaft.

7. In a machine having a rotary shaft portion projecting therefrom, acombination comprising: pump means including a runner element mounted onsaid shaft portion to turn and move axially therewith and volute elementperipherally surrounding said runner element; stationary casing meanssealingly enclosing said pump means and having internal partition meanscoacting with said volute and runner element to form an inlet chamberand a liquid discharge chamber for said volute element, said stationarycasing having oppositely disposed Wall portions extending substantiallyparallel to said shaft and a longitudinally extending slot in each wallportion; and a pair of radially opposed flanges provided on theperiphery of said volute element in slidable keyed engagement with saidslots in said wall portions for nonrotatably supporting said voluteelement for limited movement axially of said shaft.

8. In a machine having a rotary shaft portion projecting therefrom, acombination comprising: pump means including a runner element mounted onsaid shaft portion to turn and move axially therewith and a voluteelement peripherally surrounding said runner element; stationary casingmeans sealingly enclosing said pump means and having internal partitionmeans coacting with said volute and runner elements to form an inletchamber and a liquid discharge chamber for said volute element, saidstationary casing having oppositely disposed wall portions extendingsubstantially parallel to said shaft and a longitudinally extending slotin each wall portion; volute support means provided on the periphery ofsaid volute element in slidable engagement with said slots in said Wallportions for nonrotatably supporting said volute element for limitedmovement axially of said shaft; and sealing means interposed between andoperatively uniting said runner and volute element for rotation of theformer relative to the latter.

9. In a machine having a rotary shaft portion projecting therefrom, acombination comprising: pump means including a runner element mounted onsaid shaft portion to turn and move axially therewith and a voluteelement peripherally surrounding said runner element; stationary casingmeans sealingly enclosing said pump means and having internal partitionmeans coacting with said volute and runner element to form an inletchamber and a liquid discharge chamber for said volute element, saidstationary casing having oppositely disposed wall portions extendingsubstantially parallel to said shaft and a longitudinally extending slotin each wall portion; flange means provided on said volute element inslidable keyed engagement with said slots in said wall portions fornonrotatably supporting said volute element for limited movement axiallyof said shaft; and sealing means interposed between and operativelyuniting said runner and volute element for rotation of the formerrelative to the latter.

10. In a machine having a rotary shaft portion projecting therefrom, acombination comprising: pump means including a runner element mounted onsaid shaft portion to turn and move axially therewith and volute elementperipherally surrounding said runner element; stationary casing meanssealingly enclosing said pump means and having internal partition meanscoacting with said volute and runner element to form an inlet chamherand a liquid discharge chamber for said volute element, said stationarycasing having oppositely disposed Wall portions extending substantiallyparallel to said shaft and a longitudinally extending slot in each wallportion; a pair of radially opposed flanges provided on the periphery ofsaid volute element in slidable keyed arrangement with said slots insaid wall portions for nonrotatably supporting said volute element forlimited movement axially of said shaft; and sealing means interposedbetween and operatively uniting said runner and volute element forrotation of the former relative to the latter.

(References on following page) ReferencesCited in the file of thispatent UNITED STATES PATENTS Guy Nov. 23, 1909 Ross --Feb. 11, 1919Schmidt Feb. 15, 1927 Ames Apr. 5, 1927 Alsenstein Oct. 15, 1935 8Sheppard May 4, 1948 Conery Apr. 12, 1949 Conery --July 15, 1952 FOREIGNPATENTS Great Britain Feb. 10, 1949 Great Britain Mar. 14, 1949

